Thread-gage.



No. 870,286. PATEN-TBDNOV. 5, 1907.v B. M. W. HANSON.

THREAD GAGE.

APPLIOATION FLBD Nov. s. 1904.

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No. 870,286. PATENTED NOV. 5, 1907. B. M. WQ HANSON.

THREAD GAGE.'

APPLIOAT'ION FILED Nov. 8. 1904.

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BENGT M. W. HANSON, OF HARTFORD, CONNECTICUT, ASSIGNOR TO PRATT d; WHITNEY COM- PANY, OF HARTFORD, CONNECTICUT, A CORPORATION OF NEW JERSEY.

THREAD-GAGE.

Patented Nov. 5, 1907'.

Application filed November 8. 1904. Serial No. 231,912.

To all whom it may concern:

Be it known that LBENGT M. W. HANsoN, a citizen of Sweden, residing at Hartford, in the county of Hartfoid and State of Connecticut, have invented certain 5 new and useful Improvements in Thread-Gages, of

which the following is a specification.

This invention relates to thread-gages.

Heretofore the templets and plugs of said gages have been made of unhardened rings of tool-steel, and also l of hardened tool-steel. In case-hardening these old styles of plugs and templets continual trouble has been experienced due to the warping of the rings in the hardening process, whereby the perfection of the tool is destroyed, and it has to be discarded, thereby causing l vexatious loss of time and enhanced expense of manufacture.

In manufacturing either the plug or templet of my improved tool unhardened segments are preferably first formed to conform to the arc of either the periphery or 2 0 the inner side of a ring or holder by which the parts are carried, and these segments are bored through at different points, are then grooved opposite the bores to leave a sustaining portion of metal, to prevent warping during the hardening operation, and ai'e finally tapped to receive bolts for securing them in place, after which they are assembl'ed on the holder and are threaded to the standard gage required. When thus threaded and tested the segments are removed from the holder, and are subjected to the hardening operation, and after this has been accomplished the walls of the grooves are cut through to remove the sustaining webs, thereby leaving a series of key-hole slots in each segment, which will permit of a yielding movement when the segments are again secured to theholder to form the finished tool.

By practical experience it has been discovered thatthe segments will not be materially distorted during the hardening operation, and as the bearing parts of the segments are formed on an arc concentric with the bearing-surface of the ring or holder to which they are secured, should there be a slight distortion it can readily be corrected by forcing the segments against their holding-ring, the slots in said segments permitting them to yield to accomplish this result. In this way accurate tools both for inside and outside gaging of screw-threads may be obtained at less expense, thus producing an implement which for precisionized gaging capacity is perfect in construction and practical in use.

Primarily the object of the invention is the provision of an improved tool of the character mentioned for gaging either external or internal pipe-threads.

A further object of the invention is the provision of a thread-gage composed of yielding segments spaced the desired distance apart on, and firmly clamped to, the ring or holder by which they are carried.

Other features of the invention will be set forth in the following description.

In the accompanying drawings, Figure l is a plan view of one form of tool, known as the plug, involving the features of the present invention. Fig. 2 is a section on line 2 2 of Fig. l. Fig. 3 is a section on line 3 3 of Fig. l. Fig. 4 is a plan view of one of the segments, showing the grooves and the web between each of said grooves. Fig. 5 is a plan view of a casing-ring or templet involving the invention. Fig. 6 is a section on line 6 6 of Fig. 5. Fig. 7 is a plan View of a shim hereinafter described. Fig. S is a section on line 8 8 of Fig. 5, looking in the direction of the arrow; andFig. 9 is a plan view of one of the segments after it has been submitted to the hardening operation.

Like numerals designate similar parts throughout the several views.

Referring to the drawings, the numeral l designates a casting known as a plug-center, the web of said casting being slotted at 2 to afford lightness and also convenient hand-grasps. The casting is provided with a perforated hub 8, by which it may be supported on the spindle of a lathe, with a laterally-projecting rim 4, grooved circumferentially at 5, and with perforations 6 at intervals for purposes hereinafter stated, said perforations being countersunk at 6. Radial arms or spokes 7 7/ are formed by the slots 2, the arms 7 being reinforced at 8, and in these reinforced portions are internally-threaded seats 9 for the recepten of handles l0 having their ends externally-threaded at l0 to fit the seats, said handles serving as convenient means for manipulating the tool. Below the seats 6 the rirn is perforated at Il for the reception of dowel-pinshereinafter described.

Designated each by the numeral 12 are segments preferably formed of tool-steel, although they may be of other material. Each segment is concaved at l2 on an arc conforming to the periphery of the rim 4, and each is provided with a longitudinally-curved tongue 13 o'f a width snugly to fit the groove 5, although these parts may be reversed if desired.- In the manufacture of said segments each is first formed of unhardened material to the concave-convex shape illustrated Fig. 4, is tapped at 14 to receive the securing bolts, is bored at intervals at 15, is grooved at 16 opposite each bore to leave a sustaining web of metal 17, and' is bored at 18 to receive dowel-pins hereinafter described, and the segments are then assembled on their carrier and are threaded to the standard gage required. When the threading-operation is completed the segments are removed from the carrier, and are subjected to the hardening process employed, for instance case-hardening, and during this process the webs or integuments 17 prevent warping of the segments to any appreciable extent. After the hardening operation the Webs or integuments 17 are removed by a grinding or other tool, thus completing the segment and forming key-hole slots 19 therein (see Fig. l), in virtue of which the segment may yield or spring while being secured to its support.

ln assembling the segments to form the finished tool they are placed upon the plug-center at certain distances apart, as shown in Fig. 1, although these distances may be varied as desired, bolts 20 are then inserted in the periorations 6, and are threaded into the seats l4, the under sides of the heads of said bolts fitting in the countersinks 6, as shown in Fig. 3, and by tightening these bolts the segments are firmly drawn against, and are made to conform to, the shape oi the periphery of the rim 4. To prevent movement of said segments, or lost-motion due either to wear or loose fitting of the bolts 20, dowel-pins 2l are now driven into the openings 18 of the segments and the perforations 1l of the I rim 4, as illustrated in Fig. 3. It will be observed that the tongue 13 Will prevent lateral movement of the segment, and that the doWel-pin 2l will rigidly secure the segment against endwise or longitudinal motion due to loose-fitting or play oi the segment on the bolts.

Should there be a slight distortion of the segment in hardening this can readily be corrected by drawing the segment tightly against the surface of its carrier, said surface being formed on the same arc as the rear side of the segment, and on an arc concentric with the arc of the threaded part of the segment, so that should said threaded part be deflected it will be drawn back, owing to the yielding nature of the segment, into correct line. In this Way all of the segments will be clamped to their support With their threaded surfaces in perfect alinement, and a plug-gage for internal threads is the result, which is ully adapted to the use for Which it is designed and is reliable and perfect in operation.

In Figs. 5 to 9 inclusive the invention is arranged for external thread-gaging, and comprises a ring or carrier 22 provided with handles 23, said ring or carrier having a split extension at one side as at 24. Screw-bolts 25 clamp the split parts of the ring together, and a dowelpin 26 prevents movement of the same due to imperiect iitting of the threads of the screw-bolts. To alter the ring to suit requirements and bring the segments hereinafter described to proper precisionized position, shims 27 perforated at 28 to receive the doWel-pin 26 and at 29 to permit the passage of the bolts 25 are provided, as shown in Figs. l and 7.

Designated each by the numeral 30 are segments having convex backs iitting the inner circumference of the ring 22. This ring is shown of T-shape in crosssection, although the invention is not limited to any particular form, and the stem portion 22/ of the T is perforated at 222 to receive bolts 31, threaded into seats 30 in the segments While the head of the T is grooved circumierentially at 32 to receive tongues 302 on the segments, and is perforated at 33 for the passage of doWel-pins 34, which prevent circumferential movement of the segments should the bolts 31 be loose.

These segments are manufactured in precisely the same Way as the plug-segments 12,-1'. e. they are bored at 35, and grooved at 36 to leave a web 37, which Web is removed after hardening to leave key-hole slots 38, as shown in Fig. 5.

As before stated either the inner segments 30 or the outersegmcnts 12 may be spaced apart on the carrier as desired, and said segments may each be of any length consistent with accurate Working While held on the carrier,wone of the salient points ofthe invention residing in the fact that one part is rigid and the other part is yielding with relation to said rigid part to accomplish Y the result described.

Changes may be made in the form and proportions oi the parts, and the support for the gage may be different from either form shown Without departure from the invention. Furthermore, these gages may be manufactured to represent accurately the sizes and pitches of threads for all diameters, from the smallest size upward, either by the standard Briggs system or other standards, as required.

Having thus described my invention What I claim is- 1. A thread-gage comprising a carrier, a series of slotted thread-segments, having non-cutting threads; screws passing through the carrier, in threaded engagement with the segments, and serving to force them to conform to the surface of the carrier; and means independent 0f the screws for preventing movement of the segments.

2. A thread-gage comprising a circular carrier, a series of yieldable threadsegmeuts having threaded seats arranged upon the surface of said carrier, and each having a non-cutting thread; tongue-and-groove connections for preventing lateral movement of said segments; and screws passing through the carrier and engaging said seats.

3. A thread-gage comprising a circular' carrier, and a series of yieldable thread-segments conforming to the surface of the carrier; devices for securing said segments to the carrier and means independent of said devices for preventing longitudinal and lateral movement of the segments with relation to said securing devices. w

4. A thread-gage comprising a carrier, having a circular' bearing-surface, and yieldahle thread-segments shaped on their hacks to conform to said hearingsurface, and extending longitudinally thereof; screws for securing the segments in place, and thereby forcing the segments against the carrier; and devices independent of the screws and inserted in openings of the segments and carrier for preventing movement of the segments with relation to said screws.

5. A thread-gage comprising a carrier having a circular hearlngsurface, slotted non-cutting thread-gage segments, bolts for locking the segments on the carrier, and dowelpins, passing through openings in the carrier, and entering the segments for preventing movement of these segments with relation to the bolts.

G. The combination, with an annular carrier having a split-extension, of a series of thread-gage segments secured to the inner surface of said carrier; a filling-piece in the split-extension; and means for clamping the parts of said extension together.

In testimony whereof I aiix my signature in presence of two Witnesses.

B. M. W. HANSON.

Witnesses H. E. BAILEY, E. C. BENEnIc'r. 

